Theory of DNA Repair in DeinococcusA depiction of the DNA repair process that Jonathon Eisen postulates might be happening in Deinococcus radiodurans after it is exposed to radiation.View Quicktime Movie

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CLUSTAL data A CLUSTAL alignment of a segment of a gene from four species. The red letters show the amino acid sequence (R=arginine, P=proline, G=glycine, etc.). The nucleotides that are conserved in all four species are shown in the columns with an asterisk at the bottom.

Deinococcus radioduransDeinococcus radiodurans is a bacterium that scientists claim is the most radiation-resistant organism on earth.

Deinococcus radioduransDeinococcus radiodurans is a bacterium that scientists claim is the most radiation-resistant organism on earth.

Microarray experimentA. RNA is isolated from cells from two samples (in this illustration, infected and uninfected plant cells). B. The mRNA from both samples is copied to a more stable form, called cDNA, using reverse transcriptase. C. At the same time, the cDNA is labeled with fluorescent tags (a different color tag for each sample). D. The tagged cDNA is placed on the microarray chip, where it binds to the corresponding DNA that makes up the genes that have been previously spotted on the chip. E. The chip is placed in a laser scanner, which identifies the genes that hybridize to each sample (uninfected=green; infected=red; and both samples=yellow). F. The data are displayed on a computer screen where expression of the individual genes can be identified.

RNA processingA gene consists of coding regions, called exons, that are interrupted with intervening noncoding regions, called introns. During transcription, the whole segment of DNA that corresponds to a gene is copied to make RNA. During RNA processing, the introns are removed and the exons are joined. A poly(A) tail is added to the mRNA.